The literature on international students’ experiences frequently depicts them within a ‘deficient’ framework, highlighting their perceived lack of essential skills for managing their studies. Moreover, internationa...The literature on international students’ experiences frequently depicts them within a ‘deficient’ framework, highlighting their perceived lack of essential skills for managing their studies. Moreover, international students’ emotional experiences are often construed as personal and psychological attributes, with their emotions viewed as transient and pathological phases that they will eventually overcome to assimilate into the local context. However, there exists a dearth of literature investigating international students’ experiences from a sociological perspective, particularly concerning their emotional experiences within the broader social and political milieu. Utilizing a longitudinal research design to monitor 25 Chinese international postgraduates from multiple universities in London and Glasgow over the course of one year, this study illuminates the racialised, classed, and gendered dimensions of international students’ experiences in UK higher education through an exploration of their feelings of shame. Drawing on the research findings, it is evident that power relations operate insidiously and covertly to systematically frame international students’ experiences as personal or cultural ‘deficiency’. This process represents a form of misrecognition, which manifests in racialised, gendered, and classed feelings of shame, experienced at the personal level as insecurity, ‘stupidity’, exclusion, and self-doubt. Consequently, social and cultural inequalities within higher education are often situated at the individual level.展开更多
BACKGROUND: In the theory of traditional Chinese medicine,aging is mainly thought renal deficiency caused renal failure,mainly involving decline of kidney-Yang and deficiency of kidney-essence. Huanshaodan,a Chinese t...BACKGROUND: In the theory of traditional Chinese medicine,aging is mainly thought renal deficiency caused renal failure,mainly involving decline of kidney-Yang and deficiency of kidney-essence. Huanshaodan,a Chinese traditional preparation for kidney-replenishing essence,was used to be the preparation for reinforcing renal deficiency and preventing aging for aged people. OBJECTIVE: To observe the effects of Huanshaodan on swimming durance and the abilities of catalase (CAT) in serum and monoamine oxidase-B (MAO-B) in brain tissue as well as in vitro anti-oxidative ability of aging mouse. DESIGN: A controlled animal experiment. SETTING: College of Basic Medicine,Hunan University of Traditional Chinese Medicine. MATERIALS: Fifty-four healthy NIH mice,aged 18 months old,of either gender,weighing (48.9±5.4)g,and one SD male rat,aged 16 months old,weighing 51.7 g,were provided by Animal Experimental Center,Hunan University of Traditional Chinese Medicine. Thirty NIH mice were randomly chosen for swimming test,and divided into experimental group and control group,with 15 in each; The other 24 NIH mice were used for enzyme activity assay,and also divided into experimental group and control group,with 12 in each. SD rat was used for in vitro anti-oxidative ability test. Huanshaodan water decoction was composed of Cheqianzi,Wuweizi,Huaishan,Danggui,Huangbai,Shudi,Baizhi,Niuxi,Baishen,Tusizi,Buguzhi,Roucongrong and Heshouwu 13 Chinese herbs. METHODS: This study was carried out in the Second Laboratory,Department of Biochemistry,Hunan University of Traditional Chinese Medicine in June 2006. Swimming and enzyme activity assay: Mice in the two experimental groups were intragastrically administrated with 10 μL/ g Huanshaodan water decoction. Mice in the two control groups were intragastrically administrated with the same amount of normal saline. All the mice were intragastrically administrated for 5 days,and they were free to access to medicine in the other 2 days in a week. Each mouse was administrated for 8 weeks. MAIN OUTCOME MEASURES: ① Forty days after administration,mice in the experimental group and control group for swimming test were loaded at tails and allowed to swim in the water-tank. Swimming durance was recorded. ② Following the method of Chen Qi,the activities of CAT in serum and MAO-B in brain tissue as well as the inhibitory rate of each medicine on malonaldehyde (MDA) content in the in vitro rat hepatic tissue were determined; Meanwhile,the inhibitory rate of different doses of Tusizi liquid to MDA content in the rat hepatic tissue in vitro was also assayed. RESULTS: Fifty-four NIH mice and one SD rat were recruited in this experiment. Three mice died in the swimming test,and all the other animals were involved in the final analysis. ① Swimming durance of mice in the experimental group was significantly longer than that in the control group (t =7.502,P < 0.01). The activity of CAT in serum of mice in the experimental group was significantly higher than that in the control group (t =13.307,P < 0.01). ② The activity of MAO-B in brain tissue of mice in the experimental group was significantly lower than that in the control group (t =13.27,P < 0.01). ③ The inhibitory rate of Cheqianzi,Wuweizi,Huaishan,Danggui,Huangbai,Shudi,Baizhi,Niuxi,Baishen,Tusizi,Buguzhi,Roucongrong and Heshouwu 13 Chinese herbs of Huanshaodan to MDA in the rat hepatic tissue in vitro was –62.9,–95.1,–34.9,–65.1,–99.1,–87.2,–94.1,–20.0,–67.0,–83.7,–91.0,–98.4,–93.0,respectively. ④ The inhibitory rate of low to high dose of Tusizi liquid to MDA content in the rat hepatic tissue in vitro was –3.41,–18.1,–26.6,–83.7,respectively. CONCLUSION: Huanshaodan enhances swimming endurance,anti-oxygen free radical and anti-oxidativeabilities,and thus,it can delay aging.展开更多
Aiming at the defects of the nodes in the low energy adaptive clustering hierarchy(LEACH) protocol, such as high energy consumption and uneven energy consumption, a two-level linear clustering protocol is built. The p...Aiming at the defects of the nodes in the low energy adaptive clustering hierarchy(LEACH) protocol, such as high energy consumption and uneven energy consumption, a two-level linear clustering protocol is built. The protocol improves the way of the nodes distribution at random. The terminal nodes which have not been a two-level cluster head in the cluster can compete with the principle of equivalent possibility, and on the basis of the rest energy of nodes the two-level cluster head is selected at last. The single hop within the cluster and single hop or multiple hops between clusters are used. Simulation experiment results show that the performance of the two-level linear clustering protocol applied to the Hexi corridor agricultural field is superior to that of the LEACH protocol in the survival time of network nodes, the ratio of success, and the remaining energy of network nodes.展开更多
目的探讨精准经皮肝穿刺技术用于肝Ⅷ段小肝癌和脓肿治疗中应用的安全性和可行性。方法回顾性分析2017年1月至2021年5月期间新疆维吾尔自治区第三人民医院行肝穿刺治疗的肝Ⅷ段病灶患者63例的临床资料。根据肝穿刺引导方法不同分为2组:...目的探讨精准经皮肝穿刺技术用于肝Ⅷ段小肝癌和脓肿治疗中应用的安全性和可行性。方法回顾性分析2017年1月至2021年5月期间新疆维吾尔自治区第三人民医院行肝穿刺治疗的肝Ⅷ段病灶患者63例的临床资料。根据肝穿刺引导方法不同分为2组:CT+超声组(30例),接受局麻或不插管的静脉麻醉下CT联合超声引导的经皮肝穿刺置管引流/射频消融治疗;腔镜+超声组(33例),接受插管的静脉麻醉下腹腔镜联合镜下超声引导的肝穿刺置管引流/射频消融治疗。对比分析肝穿刺治疗围手术期相关指标、手术并发症发生情况、手术后患者手术和疼痛的接受程度。结果 CT+超声组较腔镜+超声组的穿刺时间短[(39.33±6.79)min vs (50.90±5.51)min]、下床时间早[(11.07±3.44)h vs (15.73±3.25)h]、术后胃肠功能恢复时间早[(8.23±1.43)h vs (14.79±3.34)h],差异均具有统计学意义(P<0.05);两组穿刺次数[(1.13±0.35)次 vs (1.09±0.29)次]、穿刺成功率[93.3%(28/30) vs 100.0%(33/33)]无统计学差异(P>0.05)。两组肝脓肿穿刺置管(分别为7例和9例)均成功,恶性肿瘤(分别为23例和24例)消融后残留率均为零。CT+超声组手术并发症总体发生率与腔镜+超声组[26.7%(8/30) vs 27.3%(9/33),χ;=0.003,P=0.118]差异无统计学意义(P>0.05);手术疼痛接受程度高于腔镜+超声组[96.7%(29/30) vs 75.7%(25/33)],差异具有统计学意义(P<0.05)。结论局麻或不插管的静脉麻醉下CT联合超声引导的精准经皮肝穿刺技术作为肝Ⅷ段小肝癌和脓肿的辅助治疗技术安全可行,可用于≤3.5 cm的病灶穿刺,可以获得与全麻下腹腔镜联合镜下超声引导的肝穿刺技术治相近的治疗效果,且手术时间更短,手术创伤更小、接受程度更高。展开更多
BACKGROUND Kabuki syndrome(KS)is a rare syndrome characterized by multisystem congenital anomalies and developmental disorder.KMT2D and KDM6A mutations were identified as the main causative genes in KS patients.There ...BACKGROUND Kabuki syndrome(KS)is a rare syndrome characterized by multisystem congenital anomalies and developmental disorder.KMT2D and KDM6A mutations were identified as the main causative genes in KS patients.There are few case reports and genetic analyses,especially of KDM6A gene mutation,in China.CASE SUMMARY This study reports a de novo KDM6A mutation in a Chinese infant with KS.A 2-month-old Chinese baby was diagnosed with KS,which manifested as hypoglycemia,congenital anal atresia at birth,feeding difficulties,hypotonia,and serious postnatal growth retardation.He died of recurrent respiratory infections at age 13 mo.DNA sequencing of his blood DNA revealed a novel KDM6A frameshift mutation(c.704_705delAG,p.N236Sfs*26)(GRCh37/hg19).CONCLUSION We present a Chinese KS patient with a novel KDM6A frameshift mutation(c.704_705delAG,p.N236Sfs*26)(GRCh37/hg19),broadening the mutation spectrum.展开更多
A newly developed descriptor, three- dimensional holographic vector of atomic interaction field (3D-HoVAIF), was used to describe the chemical structures of purine bases. After variable screening by stepwise multiple ...A newly developed descriptor, three- dimensional holographic vector of atomic interaction field (3D-HoVAIF), was used to describe the chemical structures of purine bases. After variable screening by stepwise multiple regression (SMR) technique, a partial least square (PLS) regression model was built with 3D-HoVAIF. The model was satisfactory com- paring to reference since correlation coefficients of molecular modeling ( Rc 2um), cross- validation ( Qc 2um) and standard deviation of estimation (SD) were 0.966, 0.860 and 0.112, respectively, showing that the model had favorable estimation and prediction capa- bilities. It was illustrated that information related to retention data of purine bases could preferably be expressed by 3D-HoVAIF with definite physico- chemical meanings and easy structural interpretation for purine bases. It was illustrated that 3D-HoVAIF was to preferably express retention data of purine bases and had definite physicochemical significance. So 3D-HoVAIF was a useful structural expression technique for quantitative structure activity (or prop- erty or retention) relationships (QSAR/QSPR/QSRR) study, such as structural characterization and chro- matographic retention prediction.展开更多
Support vector machine (SVM), partial least squares (PLS), and Back-Propagation artificial neural net- work (ANN) were employed to establish QSAR models of 2 dipeptide datasets. In order to validate predictive capabil...Support vector machine (SVM), partial least squares (PLS), and Back-Propagation artificial neural net- work (ANN) were employed to establish QSAR models of 2 dipeptide datasets. In order to validate predictive capabilities on external dataset of the resulting models, both internal and external validations were performed. The division of dataset into both training and test sets was carried out by D-optimal design. The results showed that support vector machine (SVM) behaved well in both calibration and prediction. For the dataset of 48 bitter tasting dipeptides (BTD), the results obtained by support vector regression (SVR) were superior to that by PLS in both calibration and prediction. When compared with BP artificial neural network, SVR showed less calibration power but more predictive capability. For the dataset of angiotensin-converting enzyme (ACE) inhibitors, the results obtained by support vector machine (SVM) re- gression were equivalent to those by PLS and BP artificial neural network. In both datasets, SVR using linear kernel function behaved well as that using radial basis kernel func- tion. The results showed that there is wide prospect for the application of support vector machine (SVM) into QSAR modeling.展开更多
A novel nano-and micro-integrated protein chip(NMIPC)that can detect proteins with ultrahigh sensitivity has been fabricated.A microfl uidic network(μFN)was used to construct the protein chips,which allowed facile pa...A novel nano-and micro-integrated protein chip(NMIPC)that can detect proteins with ultrahigh sensitivity has been fabricated.A microfl uidic network(μFN)was used to construct the protein chips,which allowed facile patterning of proteins and subsequent biomolecular recognition.Aqueous phase-synthesized,water-soluble fl uorescent CdTe/CdS core-shell quantum dots(aqQDs),having high quantum yield and high photostability,were used as the signaling probe.Importantly,it was found that aqQDs were compatible with microfluidic format assays,which afforded highly sensitive protein chips for cancer biomarker assays.展开更多
A new descriptor, called vector of topological and structural information for coded and noncoded amino acids (VTSA), was derived by principal component analysis (PCA) from a matrix of 66 topological and structural var...A new descriptor, called vector of topological and structural information for coded and noncoded amino acids (VTSA), was derived by principal component analysis (PCA) from a matrix of 66 topological and structural variables of 134 amino acids. The VTSA vector was then applied into two sets of peptide quantitative structure-activity relationships or quantitative sequence-activity modelings (QSARs/ QSAMs). Molded by genetic partial least squares (GPLS), support vector machine (SVM), and immune neural network (INN), good results were obtained. For the datasets of 58 angiotensin converting en-zyme inhibitors (ACEI) and 89 elastase substrate catalyzed kinetics (ESCK) , the R2, cross-validation R2, and root mean square error of estimation (RMSEE) were as follows: ACEI, R2cu≥0.82, Q2cu≥0.77, Ermse≤0.44 (GPLS+SVM); ESCK, R2cu≥0.84, Q2cu≥0.82, Ermse≤0.20 (GPLS+INN), respectively.展开更多
Recently, genome wide association studies showed that there is a strong association between abacavir-induced serious, idio-syncratic, adverse drug reactions (ADRs) and human leukocyte antigen-B*5701 (HLA-B*5701). Stud...Recently, genome wide association studies showed that there is a strong association between abacavir-induced serious, idio-syncratic, adverse drug reactions (ADRs) and human leukocyte antigen-B*5701 (HLA-B*5701). Studies also found that ab-acavir-induced ADRs were seldom observed in patients carrying the HLA-B*5801 subtype. HLA-B*5801 of the same sero type (B17) as B*5701 differs by only 4 amino acids from B*5701. It is believed that because of these sequence differences, HLA-B*5801 cannot bind the specific peptides which are required for HLA-B*5701 to stimulate the T cell immune response. Thus, the difference in peptide binding profiles between HLA-B*5701 and B*5801 is an important clue for exploring the mechanisms of abacavir-induced ADRs. VHSE (principal component score vector of hydrophobic, steric, and electronic properties), a set of amino acid structural descriptors, was employed to establish QSAR models of peptide-binding affinities of HLA-B*5701 and B*5801. Optimal linear SVM (support vector machine) models with high predictive capabilities were obtained for both B*5701 and B*5801. The R 2 (coefficient of determination), Q 2 (cross-validated R 2 ), and R PRE 2 (R 2 of test set) of two optimal models were 0.7530, 0.7037, 0.6153 (B*5701) and 0.6074, 0.5966, 0.5762 (B*5801), respectively. For B*5701 and B*5801, the mutations in positions 45 (MET-THR) and 46 (ALA-GLU) have little influence on the selection specificity of the P2 position of the bound peptide. However, the mutation in position 97 (VAL-ARG) greatly influences the selection specificity of the P7 position. HLA-B*5701 prefers the bulky and positively charged amino acids at the P7 position. In contrast, HLA-B*5801 prefers the non-polar hydrophobic amino acids at the P7 position while positively charged amino acids are unfavored.展开更多
文摘The literature on international students’ experiences frequently depicts them within a ‘deficient’ framework, highlighting their perceived lack of essential skills for managing their studies. Moreover, international students’ emotional experiences are often construed as personal and psychological attributes, with their emotions viewed as transient and pathological phases that they will eventually overcome to assimilate into the local context. However, there exists a dearth of literature investigating international students’ experiences from a sociological perspective, particularly concerning their emotional experiences within the broader social and political milieu. Utilizing a longitudinal research design to monitor 25 Chinese international postgraduates from multiple universities in London and Glasgow over the course of one year, this study illuminates the racialised, classed, and gendered dimensions of international students’ experiences in UK higher education through an exploration of their feelings of shame. Drawing on the research findings, it is evident that power relations operate insidiously and covertly to systematically frame international students’ experiences as personal or cultural ‘deficiency’. This process represents a form of misrecognition, which manifests in racialised, gendered, and classed feelings of shame, experienced at the personal level as insecurity, ‘stupidity’, exclusion, and self-doubt. Consequently, social and cultural inequalities within higher education are often situated at the individual level.
文摘BACKGROUND: In the theory of traditional Chinese medicine,aging is mainly thought renal deficiency caused renal failure,mainly involving decline of kidney-Yang and deficiency of kidney-essence. Huanshaodan,a Chinese traditional preparation for kidney-replenishing essence,was used to be the preparation for reinforcing renal deficiency and preventing aging for aged people. OBJECTIVE: To observe the effects of Huanshaodan on swimming durance and the abilities of catalase (CAT) in serum and monoamine oxidase-B (MAO-B) in brain tissue as well as in vitro anti-oxidative ability of aging mouse. DESIGN: A controlled animal experiment. SETTING: College of Basic Medicine,Hunan University of Traditional Chinese Medicine. MATERIALS: Fifty-four healthy NIH mice,aged 18 months old,of either gender,weighing (48.9±5.4)g,and one SD male rat,aged 16 months old,weighing 51.7 g,were provided by Animal Experimental Center,Hunan University of Traditional Chinese Medicine. Thirty NIH mice were randomly chosen for swimming test,and divided into experimental group and control group,with 15 in each; The other 24 NIH mice were used for enzyme activity assay,and also divided into experimental group and control group,with 12 in each. SD rat was used for in vitro anti-oxidative ability test. Huanshaodan water decoction was composed of Cheqianzi,Wuweizi,Huaishan,Danggui,Huangbai,Shudi,Baizhi,Niuxi,Baishen,Tusizi,Buguzhi,Roucongrong and Heshouwu 13 Chinese herbs. METHODS: This study was carried out in the Second Laboratory,Department of Biochemistry,Hunan University of Traditional Chinese Medicine in June 2006. Swimming and enzyme activity assay: Mice in the two experimental groups were intragastrically administrated with 10 μL/ g Huanshaodan water decoction. Mice in the two control groups were intragastrically administrated with the same amount of normal saline. All the mice were intragastrically administrated for 5 days,and they were free to access to medicine in the other 2 days in a week. Each mouse was administrated for 8 weeks. MAIN OUTCOME MEASURES: ① Forty days after administration,mice in the experimental group and control group for swimming test were loaded at tails and allowed to swim in the water-tank. Swimming durance was recorded. ② Following the method of Chen Qi,the activities of CAT in serum and MAO-B in brain tissue as well as the inhibitory rate of each medicine on malonaldehyde (MDA) content in the in vitro rat hepatic tissue were determined; Meanwhile,the inhibitory rate of different doses of Tusizi liquid to MDA content in the rat hepatic tissue in vitro was also assayed. RESULTS: Fifty-four NIH mice and one SD rat were recruited in this experiment. Three mice died in the swimming test,and all the other animals were involved in the final analysis. ① Swimming durance of mice in the experimental group was significantly longer than that in the control group (t =7.502,P < 0.01). The activity of CAT in serum of mice in the experimental group was significantly higher than that in the control group (t =13.307,P < 0.01). ② The activity of MAO-B in brain tissue of mice in the experimental group was significantly lower than that in the control group (t =13.27,P < 0.01). ③ The inhibitory rate of Cheqianzi,Wuweizi,Huaishan,Danggui,Huangbai,Shudi,Baizhi,Niuxi,Baishen,Tusizi,Buguzhi,Roucongrong and Heshouwu 13 Chinese herbs of Huanshaodan to MDA in the rat hepatic tissue in vitro was –62.9,–95.1,–34.9,–65.1,–99.1,–87.2,–94.1,–20.0,–67.0,–83.7,–91.0,–98.4,–93.0,respectively. ④ The inhibitory rate of low to high dose of Tusizi liquid to MDA content in the rat hepatic tissue in vitro was –3.41,–18.1,–26.6,–83.7,respectively. CONCLUSION: Huanshaodan enhances swimming endurance,anti-oxygen free radical and anti-oxidativeabilities,and thus,it can delay aging.
基金supported by the Foundation Projects in Gansu Province Department of Education under Grant No.2015A-163
文摘Aiming at the defects of the nodes in the low energy adaptive clustering hierarchy(LEACH) protocol, such as high energy consumption and uneven energy consumption, a two-level linear clustering protocol is built. The protocol improves the way of the nodes distribution at random. The terminal nodes which have not been a two-level cluster head in the cluster can compete with the principle of equivalent possibility, and on the basis of the rest energy of nodes the two-level cluster head is selected at last. The single hop within the cluster and single hop or multiple hops between clusters are used. Simulation experiment results show that the performance of the two-level linear clustering protocol applied to the Hexi corridor agricultural field is superior to that of the LEACH protocol in the survival time of network nodes, the ratio of success, and the remaining energy of network nodes.
文摘目的探讨精准经皮肝穿刺技术用于肝Ⅷ段小肝癌和脓肿治疗中应用的安全性和可行性。方法回顾性分析2017年1月至2021年5月期间新疆维吾尔自治区第三人民医院行肝穿刺治疗的肝Ⅷ段病灶患者63例的临床资料。根据肝穿刺引导方法不同分为2组:CT+超声组(30例),接受局麻或不插管的静脉麻醉下CT联合超声引导的经皮肝穿刺置管引流/射频消融治疗;腔镜+超声组(33例),接受插管的静脉麻醉下腹腔镜联合镜下超声引导的肝穿刺置管引流/射频消融治疗。对比分析肝穿刺治疗围手术期相关指标、手术并发症发生情况、手术后患者手术和疼痛的接受程度。结果 CT+超声组较腔镜+超声组的穿刺时间短[(39.33±6.79)min vs (50.90±5.51)min]、下床时间早[(11.07±3.44)h vs (15.73±3.25)h]、术后胃肠功能恢复时间早[(8.23±1.43)h vs (14.79±3.34)h],差异均具有统计学意义(P<0.05);两组穿刺次数[(1.13±0.35)次 vs (1.09±0.29)次]、穿刺成功率[93.3%(28/30) vs 100.0%(33/33)]无统计学差异(P>0.05)。两组肝脓肿穿刺置管(分别为7例和9例)均成功,恶性肿瘤(分别为23例和24例)消融后残留率均为零。CT+超声组手术并发症总体发生率与腔镜+超声组[26.7%(8/30) vs 27.3%(9/33),χ;=0.003,P=0.118]差异无统计学意义(P>0.05);手术疼痛接受程度高于腔镜+超声组[96.7%(29/30) vs 75.7%(25/33)],差异具有统计学意义(P<0.05)。结论局麻或不插管的静脉麻醉下CT联合超声引导的精准经皮肝穿刺技术作为肝Ⅷ段小肝癌和脓肿的辅助治疗技术安全可行,可用于≤3.5 cm的病灶穿刺,可以获得与全麻下腹腔镜联合镜下超声引导的肝穿刺技术治相近的治疗效果,且手术时间更短,手术创伤更小、接受程度更高。
文摘BACKGROUND Kabuki syndrome(KS)is a rare syndrome characterized by multisystem congenital anomalies and developmental disorder.KMT2D and KDM6A mutations were identified as the main causative genes in KS patients.There are few case reports and genetic analyses,especially of KDM6A gene mutation,in China.CASE SUMMARY This study reports a de novo KDM6A mutation in a Chinese infant with KS.A 2-month-old Chinese baby was diagnosed with KS,which manifested as hypoglycemia,congenital anal atresia at birth,feeding difficulties,hypotonia,and serious postnatal growth retardation.He died of recurrent respiratory infections at age 13 mo.DNA sequencing of his blood DNA revealed a novel KDM6A frameshift mutation(c.704_705delAG,p.N236Sfs*26)(GRCh37/hg19).CONCLUSION We present a Chinese KS patient with a novel KDM6A frameshift mutation(c.704_705delAG,p.N236Sfs*26)(GRCh37/hg19),broadening the mutation spectrum.
基金supported by the Industry Innovation Foundation of Shanxi Province(Grant No.2006031204)the Chongqing Applied Fundamental Science Foundation(Grant No.01-3-6).
文摘A newly developed descriptor, three- dimensional holographic vector of atomic interaction field (3D-HoVAIF), was used to describe the chemical structures of purine bases. After variable screening by stepwise multiple regression (SMR) technique, a partial least square (PLS) regression model was built with 3D-HoVAIF. The model was satisfactory com- paring to reference since correlation coefficients of molecular modeling ( Rc 2um), cross- validation ( Qc 2um) and standard deviation of estimation (SD) were 0.966, 0.860 and 0.112, respectively, showing that the model had favorable estimation and prediction capa- bilities. It was illustrated that information related to retention data of purine bases could preferably be expressed by 3D-HoVAIF with definite physico- chemical meanings and easy structural interpretation for purine bases. It was illustrated that 3D-HoVAIF was to preferably express retention data of purine bases and had definite physicochemical significance. So 3D-HoVAIF was a useful structural expression technique for quantitative structure activity (or prop- erty or retention) relationships (QSAR/QSPR/QSRR) study, such as structural characterization and chro- matographic retention prediction.
基金This work was supported by the Fok-Yingtung Educational Foundation(FYEF)(Grant No.98-7-6)the National Chun-hui Project Foundation(NCPF)(Grant No.99-04+99-37)Chongqing Applied Fundamental Science Fund(CAFS)(Grant No.01-3-6).
文摘Support vector machine (SVM), partial least squares (PLS), and Back-Propagation artificial neural net- work (ANN) were employed to establish QSAR models of 2 dipeptide datasets. In order to validate predictive capabilities on external dataset of the resulting models, both internal and external validations were performed. The division of dataset into both training and test sets was carried out by D-optimal design. The results showed that support vector machine (SVM) behaved well in both calibration and prediction. For the dataset of 48 bitter tasting dipeptides (BTD), the results obtained by support vector regression (SVR) were superior to that by PLS in both calibration and prediction. When compared with BP artificial neural network, SVR showed less calibration power but more predictive capability. For the dataset of angiotensin-converting enzyme (ACE) inhibitors, the results obtained by support vector machine (SVM) re- gression were equivalent to those by PLS and BP artificial neural network. In both datasets, SVR using linear kernel function behaved well as that using radial basis kernel func- tion. The results showed that there is wide prospect for the application of support vector machine (SVM) into QSAR modeling.
基金This work was supported by the National Natural Science Foundation(20873175 and 20725516)the Ministry of Science and Technology(2006CB933000,2007CB936000,and 2007AA06A406)the Shanghai Municipal Commission for Science and Technology(0852nm00400,0752nm021).
文摘A novel nano-and micro-integrated protein chip(NMIPC)that can detect proteins with ultrahigh sensitivity has been fabricated.A microfl uidic network(μFN)was used to construct the protein chips,which allowed facile patterning of proteins and subsequent biomolecular recognition.Aqueous phase-synthesized,water-soluble fl uorescent CdTe/CdS core-shell quantum dots(aqQDs),having high quantum yield and high photostability,were used as the signaling probe.Importantly,it was found that aqQDs were compatible with microfluidic format assays,which afforded highly sensitive protein chips for cancer biomarker assays.
基金the Foundations of National High Technology (863) Programme (Grant No. 2006AA02Z312)State New Drug Project (Grant No. 1996ND1035A01)+4 种基金Fok- Yingtung Educational Foundation (Grant No. 980706)State Key Laboratory of Chemo/Biosensing and Chemometrics Foundation (Grant No. KLCB005-0012)Chongqing University Innovation Fund (Grant No. CUIF030506)Chongqing Mu-nicipality Applied Science Fund (Grant No. CASF01-3-6)Momentous Juche Innovation Fund for Tackle Key Problem Items (Grant No. MJIF 06-9-9)
文摘A new descriptor, called vector of topological and structural information for coded and noncoded amino acids (VTSA), was derived by principal component analysis (PCA) from a matrix of 66 topological and structural variables of 134 amino acids. The VTSA vector was then applied into two sets of peptide quantitative structure-activity relationships or quantitative sequence-activity modelings (QSARs/ QSAMs). Molded by genetic partial least squares (GPLS), support vector machine (SVM), and immune neural network (INN), good results were obtained. For the datasets of 58 angiotensin converting en-zyme inhibitors (ACEI) and 89 elastase substrate catalyzed kinetics (ESCK) , the R2, cross-validation R2, and root mean square error of estimation (RMSEE) were as follows: ACEI, R2cu≥0.82, Q2cu≥0.77, Ermse≤0.44 (GPLS+SVM); ESCK, R2cu≥0.84, Q2cu≥0.82, Ermse≤0.20 (GPLS+INN), respectively.
基金supported by the National Natural Science Foundation of China (Grant No. 61073135)Chongqing Natural Science Foundation(Grant No. CSTC, 2009BA5068)
文摘Recently, genome wide association studies showed that there is a strong association between abacavir-induced serious, idio-syncratic, adverse drug reactions (ADRs) and human leukocyte antigen-B*5701 (HLA-B*5701). Studies also found that ab-acavir-induced ADRs were seldom observed in patients carrying the HLA-B*5801 subtype. HLA-B*5801 of the same sero type (B17) as B*5701 differs by only 4 amino acids from B*5701. It is believed that because of these sequence differences, HLA-B*5801 cannot bind the specific peptides which are required for HLA-B*5701 to stimulate the T cell immune response. Thus, the difference in peptide binding profiles between HLA-B*5701 and B*5801 is an important clue for exploring the mechanisms of abacavir-induced ADRs. VHSE (principal component score vector of hydrophobic, steric, and electronic properties), a set of amino acid structural descriptors, was employed to establish QSAR models of peptide-binding affinities of HLA-B*5701 and B*5801. Optimal linear SVM (support vector machine) models with high predictive capabilities were obtained for both B*5701 and B*5801. The R 2 (coefficient of determination), Q 2 (cross-validated R 2 ), and R PRE 2 (R 2 of test set) of two optimal models were 0.7530, 0.7037, 0.6153 (B*5701) and 0.6074, 0.5966, 0.5762 (B*5801), respectively. For B*5701 and B*5801, the mutations in positions 45 (MET-THR) and 46 (ALA-GLU) have little influence on the selection specificity of the P2 position of the bound peptide. However, the mutation in position 97 (VAL-ARG) greatly influences the selection specificity of the P7 position. HLA-B*5701 prefers the bulky and positively charged amino acids at the P7 position. In contrast, HLA-B*5801 prefers the non-polar hydrophobic amino acids at the P7 position while positively charged amino acids are unfavored.
